SLOW_CHARGE_RECOVERY_ACTIVE
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Applicable alarms (1)
SLOW_CHARGE_RECOVERY_ACTIVE
Likely outcomes — click to expand
Based on 284 missions where this alarm fired in the last 90 days as of 2026-10-13
Grounding vs discrepancy (of 4 ZERP issues filed on these missions)
Frequently co-occurring alarms (% of the 284 missions above)
Aggregated from fleet operations and refreshed daily. Individual outcomes may vary by site and configuration.
Background
Section titled “Background”Repeated charge-start failures first set SLOW_CHARGE_RECOVERY_ACTIVE. The Aircraft retries charging over a 24-hour recovery window and the dock will try to restart its charger service. If the recovery window expires without a successful charge-start attempt, MAX_RETRY_ATTEMPTS_FAILED sets.
The default action for an active slow-recovery alarm is to leave the Aircraft docked and allow recovery to continue. If the asset needs to be restored before the 24-hour recovery window expires, use this guide to troubleshoot the underlying Dock or Aircraft charging issue.
Troubleshooting Steps
Section titled “Troubleshooting Steps”graph TD
slow-charge-recovery-active-context{"<small><b>Step 1</b></small><br/>Question: SLOW_CHARGE_RECOVERY_ACTIVE means t..."}
allow-slow-charge-recovery-to-continue["<small><b>Step 2</b></small><br/>Action: Leave the Aircraft docked and allow s..."]
troubleshoot-active-slow-charge-recovery["<small><b>Step 3</b></small><br/>Action: If the asset needs to be restored bef..."]
load-charging-alarm-plot["<small><b>Step 4</b></small><br/>Telemetry: Load the charging alarm plot for the ..."]
check-dock-degraded{"<small><b>Step 5</b></small><br/>Question: At the charge-start failure time you ..."}
select-charging-alarm{"<small><b>Step 6</b></small><br/>Question: With those Dock conditions ruled out,..."}
restart-charger-service-for-faulted-status{"<small><b>Step 7</b></small><br/>Question: The Dock charger reported FAULTED, ..."}
power-cycle-aircraft-after-dock-charger-clears["<small><b>Step 8</b></small><br/>Action: With the Dock charger fault cleared, ..."]
follow-dock-charger-alarm-guide["<small><b>Step 9</b></small><br/>Action: Follow the Dock charger alarm topic s..."]
charger-fault-status-escalate-dock-embedded{{"<small><b>Step 10</b></small><br/>Escalation: Escalate to P2 Dock Embedded On Call...."}}
unexpected-charge-voltage-escalate-firmware-power{{"<small><b>Step 11</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call..."}}
relay-open-escalate-dock-hardware{{"<small><b>Step 12</b></small><br/>Escalation: Escalate to P2 Dock Hardware On Call...."}}
relay-close-restart-charger-service["<small><b>Step 13</b></small><br/>Action: Restart the Dock charger service/p..."]
relay-close-escalate-dock-hardware{{"<small><b>Step 14</b></small><br/>Escalation: Escalate to P2 Dock Hardware On Call...."}}
failed-to-ramp-redock-aircraft["<small><b>Step 15</b></small><br/>Action: Redock the same Aircraft on the same ..."]
failed-to-ramp-did-redock-resolve{"<small><b>Step 16</b></small><br/>Question: Did redocking start charging normally..."}
failed-to-ramp-inspect-fin-pins-distro["<small><b>Step 17</b></small><br/>Action: Complete the UMM detailed battery in..."]
failed-to-ramp-were-issues-found{"<small><b>Step 18</b></small><br/>Question: Did the battery/distro or docking-fin..."}
failed-to-ramp-escalate-aircraft-hardware{{"<small><b>Step 19</b></small><br/>Escalation: Escalate to P2 Aircraft Hardware On C..."}}
failed-to-ramp-create-dock-charger-work-order["<small><b>Step 20</b></small><br/>Action: Create a work order to replace the ch..."]
charge-timeout-escalate-dock-hardware{{"<small><b>Step 21</b></small><br/>Escalation: Escalate to P2 Dock Hardware On Call...."}}
troubleshoot-dock-charging-issue["<small><b>Step 22</b></small><br/>Action: Treat the Dock condition as the prima..."]
did-charging-start-after-reset{"<small><b>Step 23</b></small><br/>Question: Did charging start normally after the..."}
return-to-service-after-charging-starts["<small><b>Step 24</b></small><br/>Action: Return the Aircraft to service."]
escalate-to-firmware-power-after-reset{{"<small><b>Step 25</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call..."}}
escalate-to-firmware-power{{"<small><b>Step 26</b></small><br/>Escalation: Escalate to P2 Firmware Power On Call..."}}
slow-charge-recovery-active-context -->|Allow slow recovery to cont...| allow-slow-charge-recovery-to-continue
slow-charge-recovery-active-context -->|Troubleshoot now| troubleshoot-active-slow-charge-recovery
troubleshoot-active-slow-charge-recovery --> load-charging-alarm-plot
load-charging-alarm-plot --> check-dock-degraded
check-dock-degraded -->|Dock was DEGRADED| troubleshoot-dock-charging-issue
check-dock-degraded -->|UNEXPECTED_CHARGER_FAULT_S...| restart-charger-service-for-faulted-status
check-dock-degraded -->|UNEXPECTED_CHARGER_FAULT_S...| charger-fault-status-escalate-dock-embedded
check-dock-degraded -->|No Dock condition above is ...| select-charging-alarm
select-charging-alarm -->|UNEXPECTED_CHARGE_VOLTAGE| unexpected-charge-voltage-escalate-firmware-power
select-charging-alarm -->|DOCK_RELAY_FAILED_TO_OPEN| relay-open-escalate-dock-hardware
select-charging-alarm -->|DOCK_RELAY_FAILED_TO_CLOSE| relay-close-restart-charger-service
select-charging-alarm -->|FAILED_TO_RAMP_CURRENT| failed-to-ramp-redock-aircraft
select-charging-alarm -->|CHARGE_CURRENT_TIMEOUT| charge-timeout-escalate-dock-hardware
select-charging-alarm -->|No related charging alarm i...| escalate-to-firmware-power
restart-charger-service-for-faulted-status -->|Yes| power-cycle-aircraft-after-dock-charger-clears
restart-charger-service-for-faulted-status -->|No| follow-dock-charger-alarm-guide
power-cycle-aircraft-after-dock-charger-clears --> did-charging-start-after-reset
relay-close-restart-charger-service --> relay-close-escalate-dock-hardware
failed-to-ramp-redock-aircraft --> failed-to-ramp-did-redock-resolve
failed-to-ramp-did-redock-resolve -->|Yes| return-to-service-after-charging-starts
failed-to-ramp-did-redock-resolve -->|No| failed-to-ramp-inspect-fin-pins-distro
failed-to-ramp-inspect-fin-pins-distro --> failed-to-ramp-were-issues-found
failed-to-ramp-were-issues-found -->|Yes| failed-to-ramp-escalate-aircraft-hardware
failed-to-ramp-were-issues-found -->|No| failed-to-ramp-create-dock-charger-work-order
troubleshoot-dock-charging-issue --> did-charging-start-after-reset
did-charging-start-after-reset -->|Yes| return-to-service-after-charging-starts
did-charging-start-after-reset -->|No| escalate-to-firmware-power-after-reset
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style troubleshoot-active-slow-charge-recovery fill:#dcfce7,stroke:#22c55e,color:#14532d
style check-dock-degraded fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
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style follow-dock-charger-alarm-guide fill:#dcfce7,stroke:#22c55e,color:#14532d
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style unexpected-charge-voltage-escalate-firmware-power fill:#fef3c7,stroke:#f59e0b,color:#78350f
style relay-open-escalate-dock-hardware fill:#fef3c7,stroke:#f59e0b,color:#78350f
style relay-close-restart-charger-service fill:#dcfce7,stroke:#22c55e,color:#14532d
style relay-close-escalate-dock-hardware fill:#fef3c7,stroke:#f59e0b,color:#78350f
style failed-to-ramp-redock-aircraft fill:#dcfce7,stroke:#22c55e,color:#14532d
style failed-to-ramp-did-redock-resolve fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style failed-to-ramp-inspect-fin-pins-distro fill:#dcfce7,stroke:#22c55e,color:#14532d
style failed-to-ramp-were-issues-found fill:#dbeafe,stroke:#3b82f6,color:#1e3a5f
style failed-to-ramp-escalate-aircraft-hardware fill:#fef3c7,stroke:#f59e0b,color:#78350f
style failed-to-ramp-create-dock-charger-work-order fill:#dcfce7,stroke:#22c55e,color:#14532d
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style troubleshoot-dock-charging-issue fill:#dcfce7,stroke:#22c55e,color:#14532d
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style escalate-to-firmware-power-after-reset fill:#fef3c7,stroke:#f59e0b,color:#78350f
style escalate-to-firmware-power fill:#fef3c7,stroke:#f59e0b,color:#78350f Hover or focus a block to preview it. Select the block to keep the preview open.
1 question
SLOW_CHARGE_RECOVERY_ACTIVE means the Aircraft failed its first 5 charge-start attempts and is periodically retrying over a 24-hour slow recovery window. The default action is to leave the Aircraft docked and allow slow charge recovery to continue. Do not power cycle the Aircraft just to clear the retry counter while recovery is active. Do you want to wait for recovery or troubleshoot now to restore the asset? 2 action
Leave the Aircraft docked and allow slow charge recovery to continue for up to 24 hours. If charging starts and the charging alarms clear, return the Aircraft to service. If
MAX_RETRY_ATTEMPTS_FAILED sets, follow MAX_RETRY_ATTEMPTS_FAILED. 3 action
If the asset needs to be restored before the 24-hour slow recovery window expires, treat the active
SLOW_CHARGE_RECOVERY_ACTIVE alarm as a persistent charge-start failure for troubleshooting. Open the Aircraft/Droid Alarm Report and note the Zip ID, Dock ID, mission identifier, and dock_asset_id. 4 telemetry
Load the charging alarm plot for the charging session span active on the dock at the time the alarm was set. The plot shows
SLOW_CHARGE_RECOVERY_ACTIVE, MAX_RETRY_ATTEMPTS_FAILED if recovery expired, and the related /distro_a.zip_charge_interface alarms around the failed charge-start attempts. Use the Dock condition or related charging alarm at the charge-start failure time to choose the next branch. Enter the charging span ID above to load the plot.
5 question
At the charge-start failure time you are troubleshooting, compare the plot with Detailed Dock Status and Alarms. Which Dock condition is present?
6 question
With those Dock conditions ruled out, which remaining charge-interface symptom is set in the plot?
7 question
The Dock charger reported
FAULTED, but the Dock did not become DEGRADED. Restart the Dock charger service once. Did the Dock charger fault status and UNEXPECTED_CHARGER_FAULT_STATUS clear? 8 action
With the Dock charger fault cleared, power cycle the Aircraft to clear the distro retry counter, then attempt charging again.
9 action
Follow the Dock charger alarm topic shown in Detailed Dock Status and Alarms. Start with OTHER_CHARGER_FAULT if that is the active charger alarm; otherwise use the specific charger alarm topic listed in CHARGER_SERVICE_STATE_FAULTED_UNRECOVERABLE. If the selected guide clears the Dock charger fault, power cycle the Aircraft to clear the distro retry counter before retesting charge. If the selected guide ends in escalation, use that guide's escalation path and include the
max_retry_attempts_failed plot. 10 escalation
Escalate to P2 Dock Embedded On Call. The charger fault status signal is missing or not being transmitted. Include the Zip ID, Dock ID, mission identifier, and the
max_retry_attempts_failed plot. 11 escalation
Escalate to P2 Firmware Power On Call. Include the Zip ID, Dock ID, mission identifier, and the
max_retry_attempts_failed plot showing UNEXPECTED_CHARGE_VOLTAGE at the failure time. 12 escalation
Escalate to P2 Dock Hardware On Call. Include the Zip ID, Dock ID, mission identifier, and the
max_retry_attempts_failed plot showing DOCK_RELAY_FAILED_TO_OPEN. 13 action
Restart the Dock charger service once and record whether
DOCK_RELAY_FAILED_TO_CLOSE clears. 14 escalation
Escalate to P2 Dock Hardware On Call. Include the Zip ID, Dock ID, mission identifier, whether restarting the charger service cleared the alarm, and the
max_retry_attempts_failed plot. 15 action
Redock the same Aircraft on the same Dock and attempt charging again.
16 question
Did redocking start charging normally and clear the charge-start failure?
17 action
Complete the UMM detailed battery inspection, focusing on the battery-to-distro harness, connectors, and charge-contact path. For the docking-fin side, use UMM 32.1 Docking Fin Maintenance Instructions and inspect the visible contacts/pins for damage, contamination, or shorts.
18 question
Did the battery/distro or docking-fin inspection find an issue?
19 escalation
Escalate to P2 Aircraft Hardware On Call. Include the Zip ID, Dock ID, mission identifier, inspection findings, and the
max_retry_attempts_failed plot. 20 action
Create a work order to replace the charger on the Dock. Keep the Dock out of service until the charger replacement work order is complete.
21 escalation
Escalate to P2 Dock Hardware On Call. Include the Zip ID, Dock ID, mission identifier, and the
max_retry_attempts_failed plot showing CHARGE_CURRENT_TIMEOUT. 22 action
Treat the Dock condition as the primary failure.
1. Place the Dock into diagnostic mode.
2. Trigger a log offload.
3. Inspect Detailed Dock Status and Alarms.
4. Follow Operations Mode = DEGRADED for the degraded Dock. If Detailed Dock Status shows charger service state
5. Once the Dock issue is repaired or cleared for retest, power cycle the Aircraft to clear the distro retry counter, then attempt charging again.
1. Place the Dock into diagnostic mode.
2. Trigger a log offload.
3. Inspect Detailed Dock Status and Alarms.
4. Follow Operations Mode = DEGRADED for the degraded Dock. If Detailed Dock Status shows charger service state
FAULTED_UNRECOVERABLE, follow CHARGER_SERVICE_STATE_FAULTED_UNRECOVERABLE and the charger alarm topic it points to.5. Once the Dock issue is repaired or cleared for retest, power cycle the Aircraft to clear the distro retry counter, then attempt charging again.
23 question
Did charging start normally after the zip power cycle?
24 action
Return the Aircraft to service.
25 escalation
Escalate to P2 Firmware Power On Call. Include the Zip ID, Dock ID, mission identifier, the redock result, and the
max_retry_attempts_failed plot. 26 escalation
Escalate to P2 Firmware Power On Call. Include the Zip ID, Dock ID, mission identifier,
/distro_a.zip_charge_interface.num_failed_handshake_attempts, the active SLOW_CHARGE_RECOVERY_ACTIVE alarm report, and the max_retry_attempts_failed plot.Resolution note
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